Cassia seed comes from an upright-growing plant called cassia or jue ming zi that is native to tropical regions. It is extremely popular in China and is grown in several provinces, such as Anhui, Sichuan, Guangxi, and Guangdong. The plant can grow as high as four feet (1.2 m), has yellow flowers and large leaves that group together with six leaves per group. It has pods that are about 20 centimeters (7.9 in) in length and contain the seeds of the cassia plant. The seeds are smooth to the touch and range from green to deep brown, sometimes with a yellow stripe.

It is easy to grow the cassia plant. In a greenhouse, sow the seeds during the early spring months. Then, move the seedlings to the outdoor gardens when the soil thaws and the temperatures become warmer. It is best to plant the seedlings 60 centimeters (23.6 in) apart. Once a pod forms, the seeds can be harvested – usually during the fall months. They are typically sun-dried before they are used.

The importance of the cassia seed is far reaching, especially for those interested in Chinese medicine. It can be used for medicinal purposes, for dying, and even as an alternative to coffee. It can be found in many forms ranging from a whole seed, to ground powders, tea packets, pastes, and herb pillows.

The most popular use of cassia seed is for medicinal purposes. It most commonly treats problems with the liver, kidney, intestinal, and vision. For example, it can be used to treat constipation and remove heat from the liver. Cassia seed paste is popular to treat various skin disorders and other parasites, such as ringworm.

Sometimes the root of the cassia plant is dried and made into paste, as well, to treat ringworm and venomous snake bites. The seed can be used to treat blurry vision and irritated eyes, as well. In addition, some practitioners use it to lower blood pressure; however, people who are already taking medicine to control high blood pressure should not take cassia seed.

The dosage of cassia seed varies from six (.21 oz) to 12 grams (.42 oz), depending on the size of the person, the ailment that is being treated, and whether the cassia seed is combined with other herbs, seeds, or roots. Higher concentrations can be used if the cassia seed is used without other medicines. These larger doses can reach up to 30 grams (1.05 oz). It is important to discuss any herbal medications, including cassia seed, with a licensed doctor before consuming them.